Corneal endothelial cell density and morphology in Chinese patients with pseudoexfoliation syndrome

AIM: To evaluate the corneal endothelial cell density and morphology in Chinese patients with pseudoexfoliation syndrome (PEX). METHODS: Medical records of 16 patients (20 eyes) with PEX who presented to our institution between July 2008 and June 2010 were retrospectively reviewed. Thirteen eyes had combined glaucoma. The information of five apparently normal fellow eyes in these patients was also recorded. Left eyes of 20 patients with bilateral senile cataracts but no other eye disease were included as controls. Specular microscopy was performed in all eyes to analyze for corneal endothelial cell density and morphology. Cell density, coefficient of variation in cell size, and percentage of hexagonal cells in corneal endothelium were evaluated. RESULTS: The mean corneal endothelial cell density in the PEX eyes was 2298+/- 239 cells/mm(2), significantly lower than that in the cataract eyes (2652+/- 18 cells/mm(2), P=0.026), but there were no significant differences in coefficient of variation of cell size and frequency of hexagonality between these two groups. No significant differences in the three parameters were found between the apparently normal fellow eyes and the PEX eyes or the cataract eyes, or between the PEX eyes with and without glaucoma. CONCLUSION: Corneal endothelial cell density may decrease in Chinese patients with PEX. The development of glaucoma in PEX eyes does not seem to be related with the change in corneal endothelial cell density or morphology.

Characteristics of corneal aberration in patients with bilateral keratoconus and unilateral corneal Vogt’s striae

AIM:To assess the corneal high-order aberration(HOA)and its correlation with corneal morphological parameters in patients with bilateral keratoconus(KCN)and unilateral Vogt’s striae.METHODS:A total of 168 eyes of 84 patients with KCN,whose corneas had definite signs of unilateral Vogt’s striae,were enrolled.Corneal HOA and morphological parameters were measured using Pentacam HR.RESULTS:The corneal morphological parameters between KCN eyes with and without Vogt’s striae were evidently different(P<0.001).The 3rd coma 90°,4th spherical aberration,5th coma 90°,root-mean-square(RMS)(total),and RMS(HOA)in the front,back surfaces and total cornea in KCN eyes with Vogt’s striae were significantly higher than those in KCN eyes without Vogt’s striae(P<0.001).In KCN eyes with Vogt’s striae,the 3rd coma 90°and 4th spherical aberration in the front surface and total cornea were negatively correlated with flat keratometry value(K1),steep keratometry value(K2),mean keratometry value(Km),maximum keratometry value(Kmax),anterior corneal elevation(ACE),and posterior corneal elevation(PCE;P<0.05).The 3rd coma 90°,4th spherical aberration in back surface and RMS(total),RMS(HOA)in the front,back surfaces,total cornea were positively correlated with K1,K2,Km,Kmax,ACE,and PCE(P<0.05).CONCLUSION:Corneal HOA especially vertical coma and spherical aberration may increase when Vogt’s striae appeared in KCN eyes.The scale of increase is significantly related with changes in corneal shapes.